smartgame/js/entities/BrokenPlatform.js

import Entity from "../Entity.js";
import {Trait} from "../Entity.js";
import Texture from "../Texture.js";
import Tile from "../Tile.js";
import Shaker from "../Shaker.js";
import Vec2 from "../Vec2.js";
import assets from "../assets.js";

import TPlatform from "../traits/TPlatform.js";
import TCollider from "../traits/TCollider.js";
import TPhysics from "../traits/TPhysics.js";

class Behavior extends Trait {
	constructor(entity) {
		super(entity, "behavior");

		this.shaker = new Shaker();
		this.shake = 0;
		this.shakeAccel = 14;
		this.reliableTime = 1;
		this.resetTime = 4;

		this.state = 0;
		this.timer = 0;
	}

	init() {
		this.initialPos = this.entity.pos.clone();
		this.entity.t.physics.enabled = false;
	}

	reset() {
		this.entity.t.physics.enabled = false;
		this.shake = 0;
		this.entity.t.physics.velocity.set(0, 0);
		this.entity.pos.set(this.initialPos.x, this.initialPos.y);

		this.state = 0;
		this.timer = 0;
	}

	update(dt) {
		if (this.state === 0) {
			this.entity.t.collider.entities.forEach(e => {
				let fall =
					e.has("physics") &&
					e.bounds.intersectSide(this.entity.bounds) === "top";

				if (fall) {
					this.timer = this.reliableTime;
					this.state = 1;
				}
			});
		}

		if (this.state === 1) {
			this.shaker.shake(this.shake);
			this.shake += this.shakeAccel * dt;
			this.timer -= dt;

			if (this.timer <= 0) {
				this.entity.t.physics.enabled = true;
				this.state = 2;
				this.timer = this.resetTime;
			}
		} else if (this.state === 2) {
			this.timer -= dt;

			if (this.timer <= 0) {
				this.reset();
			}
		}

		this.shaker.update(dt);
	}
}

export default class BrokenPlatform extends Entity {
	constructor(level, width = 5) {
		super(level, "platform");

		this.bounds.size.set(width, 0.5);
		this.addTrait(new TCollider(this));
		this.addTrait(new TPlatform(this));
		this.addTrait(new TPhysics(this));
		this.addTrait(new Behavior(this));

		this.texture = new Texture(assets.tiles, Tile.createLine(
			Vec2.zero, this.bounds.size.x,
			"broken-platform"));
	}

	draw(ctx) {
		let shaker = this.t.behavior.shaker;

		this.texture.draw(
			ctx,
			this.pos.pixelX + shaker.vec.pixelX,
			this.pos.pixelY + shaker.vec.pixelY);
	}
}